Electric current rectifier



UHU

BYQl/mw MMMWM ATTORNEYS Jan. 29, 1935. s. RUBEN 9 ELECTRIC CURRENT RECTIFIER Filed June 18, 1932 Patented Jan. 29, 1935 t v ELECTRIC CURRENT RECTIFIER Samuel Ruben, New Rochelle, N. Y., assignor to Ruben Rectifier Corporation, Englewood, N. J., a corporation of Delaware Application June 18, 1932, Serial No. 617,960

` 2a claims. (ci. irs-ass) This invention relates to electric current rectitures of construction combination of elements; fiers and the like which employ asymmetric andarrangement of parts, which willbe exem: couples of the dry surface contact variety and, plified in the constructions hereinafter set forth more particularly, to such couples including one and the scope of the application of which will be electrode element of a relatively electropositive indicated in the claims.

material and another electrode element of a rela- Fig. 1 is a top View of one form of thedetively electronegative material adapted to covice of the present invention; l operatewith the former for the electrochemical Fig. 2 is a sectional view on line 2-2 of Fig. 1; formation and maintenance at their junction of Fig. 3 is a bottom view of the device depicted an inverse current-blocking film.l in Figs. 1 and 2;

General objects of the invention are the pro- Fig. 4 is a sectional view of a modication of visions of such a device having improvedfcharthe device depicted in Figs. 1 and v2; acteristics and which is eicient, economical and Fig. 5 is a view partly in section and partly in readily manufactured; anelectropositive electrode elevation of a modification of the device of the l5 element thereof having improved electrical charpresent invention; and 15 acteristics; and structural embodiments of the de- Fig. 6 is an elevational view of another modivice which are readily constructed and allow iication of the device of the present invention, eicient use and operation of the device. with parts broken away.

A more specific object of the invention is the Prior to the present invention electrical curprovision of vsuch a device wherein the electrorent rectiiiers and the like which employed asym- '20 positive electrode element of a silicon material metric couples of the dry surface-contact variety has a high contact resistance with the electro comprising a relatively electropositive electrode negative electrode element which includes a surelement and a relatively electronegative electrode face, preferably of a compound of an element element adapted to cooperate with the former for UNITED sTATEs- PATENT' OFFICE chosen from an empirical group of elements of the electrochemical formation and maintenance 25 sub-group B of Mendelejeffs periodic table of at their junction of an inverse current-blocking elements, to provide in the device a contact refilm have been provided with a contact resistance sistance sufficient to maintain an inverse currentto perform such functions by the oxidation of the blocking iilm at the .contacting surfaces resulting surfaces of the electropositive electrode element,

in a substantially equal distribution of the curthe interposition between the electrode elements 30 rent over the entire area, and to obtain chemical of a resistance layer of a film-forming'material,

stability, reduction of the resistance of the elecor by the addition of resistance coatings to the tronegative element and the amount of current electronegative electrode` element. Such units necessary to form and maintain the inverse have been frequently characterized by non-unicurrent-blocking film at the junction of the elecform operating characteristics and instability 35 trode elements, steadiness of output, and increased during operation under ordinary atmospheric efficiency. 5 conditions. These undesirable characteristics of 'Another object 0f the invention iS the provithe prior art devices are substantially eliminated sion of a simple and cheap structure including a by the present invention.

40 metallic base member provided With a DrOjeCting In accordance with the present invention a 40 portion having a surface of an electronegative device of this type is provided which has an electrode compound which cooperates with a mass electropositive electrode element formed from a of a silicon material held in position thereagainst silicon material, that is, silicon alone or a comby an insulated cup wall and a projecting portion pound of silicon and an element chosen from on a resilient member, the latter being secured an empirical group of more electropositive ele- 45 to the base by suitable means adapted to exert ments of the electrochemical table of elements sufcient pressure on the units for eilicient surpreferably chosen from the second and third face contact and operation. Y periodic groups of Mendelejeffs periodic table of A further object of the invention is the proelements, such as, for example, beryllium, magvision of a special structure whereby if desired nesium, calcium, zinc and aluminum. This elec- 50 the units of the asymmetric couple may be opertropositive electrode element is placed in surface ated in a vacuum. contact with an electronegative electrode element Other objects of the invention will in part be having a high Contact resistance with the elecobvious and will in part appear hereinafter. tropositive electrode element and is preferably The invention accordingly comprises the feaformed. from, orI provided with a surface of, a 55 compound of an element chosen from an empirical group of elements of sub-group B of the sixth periodic group in Mendelejeffs periodic table of elements such as, for example, sulphur, selenium andtellurium. The other constituents of the compound forming the electronegative material may be any suitable metal or alloy thereof chosen from an empirical group of metals or materials, such as, for example, copper, silver, brass, etc. Sufficient pressure is applied to the electrode elements to insure good contact between their adjacent surfaces and an inverse currentblocking lm is formed at the junction of the elements by allowing current to flow therethrough during the forming period. The high contact resistance of the electropositive electrode element with the electronegative electrode element maintains this inverse current-blocmng film during operation of the device.

It has been found that silicon alone may be used for the electropositive electrode material but since its internal resistance is relatively high a compound of silicon and a more electropositive material which has a lower specific resistance, such as magnesium, is preferred. The resulting compound has a lower specific resistance than that of silicon its use thus being attended by a smaller 12R loss and it has a suflicient internal resistance to obtain with the electronegative material the derised relatively high contact resistance to cause the formation of the inverse current-blocking lm when current is passed between the electropositive electrode material and the electronegative electrode material.

Silicon and silicide compounds have an additional advantage over magnesium, or compounds thereof other than magnesium silicide, in that they are chemically stable and can be operated under ordinary atmospheric conditions and without external chemical effects, such as oxidation, and consequent ineiciencies in operation.

Referring to the drawing, Figs. 1 and 2 show views of one form of the device of the present invention which consists of a metallic base member 10 of any good electrically conductive material, copper being preferred, provided with a substantially cylindrical plug l1 of electrically conductive material such as copper. If desired, this plug member 11 may be made integral with the base member 10. One face of the plug member 11 is provided with a layer 12 of a relatively electronegative material, such as, copper sulphide, which may be directly formed thereon by subjecting the face of the plug 11 to the action of sulphur vapors in a well known manner or may be formed by placing on the face of the plug member 11 a mass of granular copper sulphide the particles preferably being of a size which pass through a screen of between about 36 mesh and 60 mesh.

An insulating collar 13 is positioned over the sulphide plug ll to form a cup member having insulating Walls 14 and a bottom of a relatively electronegative material. The collar 13 may be formed from any suitable insulating material but' to prevent fracture thereof when pressure is applied to the unit is preferably formed from aluminum and coated on the inside with an insulating oxide layer. A mass 15 of a relatively electropositive material, such as a silicon material, magnesium silicide being preferred, is p0- sitioned within the collar 13,/ This mass 15 may consist of a single crystalline structure or of several small pieces of the silicide compound.

A resilient metallic member 16, preferably in the form shown to include a plurality of resilient arms 17, is provided with a substantially cylindrical projecting portion 18, preferabh of copper, adapted to project into the collar 13 and contact the mass 15. Each of the arms 17 is apertured to receive a bolt 19` of suflcient length to extend through an aperture in the base member 10, the bolt 19 being insulated from the base member 10 by an insulating collar 20. These bolts are adapted to hold 'the assembly together in a manner depicted in Fig. 2 to stress the resilient arms 17 and thus apply a sufficient pressure to the mass 15 between the plug member 11 and projecting portion 18 to insure good contact therebetween. This device is completedby securing to the base member 10 an electrical terminal 21 and mounting an additional electrical terminal 22 in electrical contact with the resilient member 16 in any desired manner.

In Fig. 4 is shown a modification of the structure depicted in Figs. 1 and 2. The base member 10', similar to the base member 10 of Fig. 2, is preferably formed from copper and integral with the plug or projecting portion 11' and is provided with a threaded shank 23. 'Ihe projecting portion 11' is provided with the surface 12 of electronegative material and the collar 13 is positioned thereover and the mass 15 of silicon material is placed therein. Another base member l0" having a projecting portion 11" and4 a threaded shank 23 is positioned as shown with the face of the projecting portion 11" in contact with the mass l5 within the collar 13. A resilient spider 24, shaped in plan view similarly to the member 16 but with the arms thereof bowed as shown, is positioned over the shank 23', and the bolts 19', extending through holes in the spider 24 and base members 10', 10", complete the assembly. These units may be arranged in series by coupling together Shanks 23 and 23' of adjacent units with internally threaded collars 25.

In Fig. 5 is shown a modification of the device wherein several asymmetric couples similar to the one depicted in Figs. 1 and 2 are arranged in series. Each of the base members 26 is formed similarly to that of member 16, each being provided, however, with a plug 27 similar to plug 11 mounted on the base member 10. Each of these plug members 24 dually perform the functions of the members 11 and 18 of the device depicted in Figs. 1 and 2 when the units of the present modification are stacked as shown with masses 15 interposed between the adjacent plug members and confined within the insulating collars 13. 'Ihrough bolts 28 secure the units of the assembly together, insulating collars 29 being used to prevent shorting of the couples, and electrical terminal members 21 and 22, each in electrical contact with an end unit, as in the rst modification. complete the assembly.

When desired, the asymmetric couple or couples may be mounted and operated in a vacuum through the use of a suitable structure, such as that shown in Fig. 6 which comprises a vacuum tube base 30 provided with terminal member supports 31 suitably secured to terminal members 32, preferably of copper. A pair of electrode elements 33 and 34 are interposed between adjacent terminal members 32-32. These units are secured together by a bolt 35 insulated from the units by a suitable insulating sleeve 36. The device shown in 6 is a double wave rectifying device, each half-wave of the alternating current being rectified by one pair of electrode elements 33 and 34. In such case the two electrode elements 33-33 are preferably formed from a pressed mass of silicide compound, such as, magnesium silicide or calcium silicide. The electrode elements 34-34 are preferably formed from copper sulphide.

In operation of the device depicted, `the silicon material electrode element forms the cathode and the copper sulphide electrode element forms the anode andwhen a currentl is passed between these electrode elements during the forming` period an inverse current-blocking film is formed therebetween. It is believed but it is by no means certain that this current-blocking film, when the anode is formed from copper sulphide and the cathode is formed from magnesium sili'- cide, is sulphides of silicon and magnesium. I do not wish, however, to be bound by this theory with regard to the probable nature of the compound forming the inverse current-blocking lm.

It will thus be seen that the present invention emciently attains the objects set forth above and provides asymmetric couples which are simple and rugged in structure and eicient in opera.

tion, units including an electropositive electrode element of a silicide of magnesium and an electronegative electrode element of a sulphide of copper having been operated at an efficiency of as high as 80 per cent. The particular structures tronegative electrode element. Such structures also allow a considerable reduction in the amount of electronegative material and a consequent reduction of the resistance of the electronegative material, a very thin layer thereof being all that is necessary for eicient operation.

The use of the expression, in electric current rectifiers and the like, an asymmetric couple is intended to cover devices which have the property of` conducting current in one direction and blocking current in the reverse direction.

Since certain changes may be made in the above constructions and different embodiments of the invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

Having described my invention, what I claim asAnew and desire to secure by Letters Patent, is:

l. A unilateral conductive electric couple comprising a body of a silicon material maintained in contact with a body of relatively electronegative material, said silicon material having a high contact resistance with said 'electronegative material and cooperating therewith for the electrothermal formation and maintenance at their junction of reactionary products formed between elements of the electropositive and electronega' 2. A unilateral conductive electric couple com` prising a'. body of a silicon material maintained the electropositive andl electronegative materialsA to act as an inverse current-blocking lm, said electronegative material including at least one electronegative compound chosen from an empirical group comprising sulphides, `selenides and tellurides.

3. A unilateral conductive electric couple comprising a body of a silicon material maintained in contact with a body of relatively electronegative material, said silicon material comprising' a silicide compound of an element chosen from an empirical group of elements of the second and third periodic groups in Mendelejeifs periodic table of elements and having a high contact resistance with said electronegative material and cooperating therewith for the electro-thermal formation and maintenance at their junction of reactionary products formed between elements of the electropositive and electronegative materials to act as an inverse current-blocking i'llm, said electronegative material including at least one electronegative compound chosen from an ernpirical group comprising sulphides, selenides and tellurides.

4. A unilateral conductive electric couple comprising a body of a silicon'material maintained in contact with a body of relatively electronegative material, said silicon material comprising a silicide compound of an element chosen from an empirical group of elements including beryllium, magnesium, calcium, zinc and aluminum, and having a high contact resistance with said electronegative material and cooperating therewith 'for the electro-thermal formation Land maintenance at their junction of reactionary products formed between elements of the electropositive and electronegative materials to act as an inverse current-blocking film, said electronegative material including at least one electronegative compound chosen from an empirical group comprising sulphides, selenides and tellurides.

5. In electric current rectifiers and the like, of the dry surface-contact variety, an asymmetric couple comprising a relatively electropositive ,electrode element of a silicon material, and a relatively electronegative electrode formed from one of the three general groups of materials, sulphides, selenides and tellurides in surface contact with said' electropositive electrode.

6. In electric current rectifiers and the like, of the dry surface-contact variety, an asymmetric couple comprising a relatively electropositive electrode element of a silicide compound of one of the elementsof the second and third periodic groups in Mendelejeffs periodic table of elements, and a relatively electronegative electrode element having a surface of an electronegative compound including an element chosen from an empirical group of elements of sub-group B of the sixth periodic group in Mendelejeffs periodic table of elements in surface contact with said electropos'tive electrode. y

7, In electric current rectiers and the like, of the dry surface-contact variety, an asymmetric couple comprising a relatively electropositivev 8. In electric current rectiers and the like, of

the dry surface-contact variety, a relatively electropositive electrode element of a silicide compound of one of the elements magnesium and calcium and a relatively electronegative electrode element of a sulphide of copper in surface contact with said electropositive electrode.

9. A unilateral conductive couple comprising a body of a silicide of magnesium maintained in contact with a sulphide of copper.

l0. A unilateral conductive couple of the dry surface-contact variety comprising a metallic base member, a projecting portion thereon having a face of a relatively electronegative compound, an insulating collar positioned over said projecting portion, a mass of a relatively electropositive compound in said collar in contact with the electronegative compound, aresilient metallic member having a portion projecting into said collar and contacting said mass, and means to secure said resilient member to said base and apply pressure to said mass.

l1. A unilateral conductive couple of the dry surface-contact variety comprising a metallic base member, a projecting portion thereon including a cup-shaped member provided with in" sulating side walls and a bottom of a relatively electronegative compound including an element chosen from an empirical group of elements of sub-group B of the sixth periodic group in Mendelejeis periodic table of elements, a mass of a silicon material disposed in said cup-shaped member, another metallic base member having a metallic projecting portion engaging said mass, and means to secure said base members together in an insulated manner and to apply pressure to said mass.

l2. A unilateral conductive couple of the dry surface-contact variety, comprising a metallic base member, a projecting portion of copper thereon the face of which consists of a compound of copper and an element chosen from an empirical group of elements including sulphur, selenium and tellurium, an insulating collar positioned over said projecting portion, a mass of a silicon material disposed in said collar in contact with the copper compound, a resilient metallic member having a portion projecting into said collar and contacting said mass, and means extending between said base and said resilient member to secure the units of the assembly together and apply pressure to said mass.

13. In electric current rectiers and the like, an asymmetric couple comprising a vacuum tube base, spaced apart terminal members supported substantially vertically on said base, a relatively electropositive 4 electrode element of a silicide compound of one of the elements of the second and third periodic groups in Mendeljeis periodic table of elements and a relatively electronegative electrode element of a relatively electronegative compound including an element chosen from an empirical group of elements of sub-group B of the sixth periodic group in Mendelejeffs periodic table of elements in surface contactwith each other positioned between said terminal members,

evacuated envelope mounted on said base and enclosing said terminal members and electrodes.

14. In electric current rectiers and the like, an asymmetric couple comprising a vacuum tube base, spaced apart metallic terminal members supported on said base, a relatively electropositive electrode element of a silicon material in contact with one of said terminal members, a relatively electronegative electrode element of electronegative material of at least one compound chosen from an empirical group comprising sulphides, selenides and tellurides in contact with the other of said terminal members and said electropositive electrode element, a member transxing said terminal members and said electrode elements adapted to hold said units in contact with each other and insulated therefrom, and an evacuated envelope mounted on said base ,and inclosing said units.

l5. In electric current rectiers and the like, the combination comprising a vacuum tube base having at least three terminal prongs, at least three substantially aligned spaced apart terminal members of electrically conductive material supported on said base each being electrically connected to one of said prongs, two pairs of electrode elements interposed between adjacent terminal members each of said pair of elements including a relatively electropositive electrode element of a silicon material and a relatively electronegative electrode element of a relatively electronegative compound including an element chosen from an empirical group of elements of subgroup B of the sixth periodic group in Mendelejels periodic table of elements, a bolt transilxing all of said terminal members and electrode elements and insulated from said units, and an evacuated envelope mounted on said base and inclosing said units.

16. A unilateral conductive electric couple comprising an electropositive electrode formed from silicon and one oi the elements beryllium, magnesium, calcium, zinc and aluminum maintained in contact with an electronegative electrode formed from one of the three general groups of materials, sulphides, selenides and tellurides.

17. A unilateral conductive electric couple comprising an electropositive electrode formed from silicon and magnesium maintained in contact with an electronegative electrode formed from one of the three general groups of materials, sulphides, selenides and tellurides.

18. A unilateral conductive electric couple comprising an electropositive electrode formed from silicon and aluminum maintained in contact with an electronegative electrode formed from one of the three general groups of materials, sulphides, selenides and tellurides.

19. A unilateral conductive electric couple comprising an electropositive electrode formed from silicon and calcium maintained in contact with an electronegative electrode formed from one of the three general groups of materials, sulphides, selenides and tellurides.

20. A unilateral conductive electric couple comprising an electropositive electrode formed from silicon and one of the elements beryllium, magnesium, calcium, zinc and aluminum maintained in contact with an electronegative electrode formed from a compound of one of the elements sulphur, selenium and tellurium wit copper.

21. A unilateral conductive electric couple com prising an electropositive electrode formed from silicon and one of the elements beryllium, magnesium, calcium, zinc and aluminum maintained 5 in contact with an electronegative electrode formed from copper sulphide.

22. A unilateral conductive elecinic couple comprising an electropositive electrode formed from silicon and one of the elements beryllium,

magnesium, calcium, zinc and aluminum maintained in contact with an electronegative electrode formed from brass sulphide.

23. A unilateral conductive electric couple com prising an electropositive electrode formed from silicon and magnesium maintained in contact with an electro-negative electrode formed from copper and sulphur.

SAMUEL RUBEN. 

